Was this some sort of prank, a hoax played by local farm boys or a demented taxidermist for fun and the attention of the press? The answer is no. 
The Lake Delavan find of May 1912 was only one of dozens and dozens of similar finds that were reported in local newspapers from 1851 forward to the present day. It was not even the first set of giant skeletons found in Wisconsin. 
On 10 August 1891, the New York Times reported that scientists from the Smithsonian Institution had discovered several large "pyramidal monuments" on Lake Mills, near Madison, Wisconsin. "Madison was in ancient days the centre of a teeming population numbering not less than 200,000," the Times said. The excavators found an elaborate system of defensive works which they named Fort Aztalan

"The celebrated mounds of Ohio and Indiana can bear no comparison, either in size, design or the skill displayed in their construction with these gigantic and mysterious monuments of earth -- erected we know not by whom, and for what purpose we can only conjecture," said the Times

On 20 December 1897, the Times followed up with a report on three large burial mounds that had been discovered in Maple Creek, Wisconsin. One had recently been opened. 

"In it was found the skeleton of a man of gigantic size. The bones measured from head to foot over nine feet and were in a fair state of preservation. The skull was as large as a half bushel measure. Some finely tempered rods of copper and other relics were lying near the bones." 

Giant skulls and skeletons of a race of "Goliaths" have been found on a very regular basis throughout the Midwestern states for more than 100 years. Giants have been found in Minnesota, Iowa, Illinois, Ohio, Kentucky and New York, and their burial sites are similar to the well-known mounds of the Mound Builder people

The spectrum of Mound builder history spans a period of more than 5,000 years (from 3400 BCE to the 16th CE), a period greater than the history of Ancient Egypt and all of its dynasties. 

There is a "prevailing scholarly consensus" that we have an adequate historical understanding of the peoples who lived in North America during this period. However, the long record of anomalous finds like those at Lake Delavan suggests otherwise. 

The Great Smithsonian Cover-Up 

Has there been a giant cover-up? Why aren't there public displays of gigantic Native American skeletons at natural history museums? 

The skeletons of some Mound Builders are certainly on display. There is a wonderful exhibit, for example, at the Aztalan State Park where one may see the skeleton of a "Princess of Aztalan" in the museum. 

But the skeletons placed on display are normal-sized, and according to some sources, the skeletons of giants have been covered up. 

Specifically, the Smithsonian Institution has been accused of making a deliberate effort to hide the "telling of the bones" and to keep the giant skeletons locked away. 

In the words of Vine Deloria, a Native American author and professor of law: 

"Modern day archaeology and anthropology have nearly sealed the door on our imaginations, broadly interpreting the North American past as devoid of anything unusual in the way of great cultures characterized by a people of unusual demeanor. The great interloper of ancient burial grounds, the nineteenth century Smithsonian Institution, created a one-way portal, through which uncounted bones have been spirited. This door and the contents of its vault are virtually sealed off to anyone, but government officials. Among these bones may lay answers not even sought by these officials concerning the deep past."

Two Giant Skeletons Near Potosi, WI 

The January 13th, 1870 edition of the Wisconsin Decatur Republican reported that two giant, well-preserved skeletons of an unknown race were discovered near Potosi, WI by workers digging the foundation of a saw mill near the bank of the Mississippi river. One skeleton measured seven-and-a-half feet, the other eight feet. The skulls of each had prominent cheek bones and double rows of teeth. A large collection of arrowheads and "strange toys" were found buried with the remains. 

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© SouthMilwaukeeNow
Giant Skeleton Discovered in Maple Creek, WI 
On December 20th, 1897 the New York Times reported that three large burial mounds had been discovered near Maple Creek, WI. Upon excavation, a skeleton measuring over nine feet from head to toe was discovered with finely tempered copper rods and other relics. 
Giant Skeleton in West Bend, WI 
A giant skeleton was unearthed outside of West Bend near Lizard Mound County Park and assembled by local farmers to a height of eight feet. More about this can be found in Washington County Paranormal: A Wisconsin Legend Trip by local author and investigator J. Nathan Couch

While a normal-sized skeleton of a supposed mound builder (the "Princess of Aztalan") is on display at the site of several large pyramidal monuments near Madison called Aztalan State Park, the goliath remains of Wisconsin's giants have vanished along with the hundreds of others discovered throughout the midwest. 

Many have accused the Smithsonian Institution of covering up these discoveries, locking the giant skeletons away and depriving the public of their findings. 

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The news no longer reports these discoveries.
I am doing research and investigation. Thank you.  
For Liberty, For Freedom 
Kristan T. Harris  

Source: http://www.sott.net/article/256712-A-giant-mystery-18-strange-giant-skeletons-found-in-Wisconsin-Sons-of-god-Men-of-renown

The Nephilim

Genesis chapter 6 tells us, "There were giants in the earth in those days".   This one little verse says quite a lot.  
What does God mean when he said there were "giants" here on Earth.  We have already seen how the pre-Flood world gave the ideal conditions for long life and huge growth, which we also know from the dinosaur, plant, insect and other fossils.  
But what about humans?  
We know they lived very long by the genealogies of Genesis (e.g. Adam lived 930 years).  Would they, too, continue to grow very large?
Ron Wyatt, on one of his first trips to the Ark site, discovered Noah's house and the grave of his wife, Mrs. Noah.  He claims the sarcophagus was 18 feet tall.  Now when we hear this, we think it to be incredulous.  
But is it really?  
What would we expect a 900 year old person to look like, who lived in a much better environment than ours?  Would we expect them to be exactly like us, or different?  
I would certainly expect them to be different.  And the Bible says "there were giants in those days".  So according to our best and most reliable source - the Bible - we should expect them to have been very large indeed (the Bible never exaggerates).
So what does the fossil record show?  
Well this is where things get interesting.  Giant ancient humans would fly in the face of evolution.  It would show that we have actually devolved, not evolved.   
Since the 1800's, there have been many written accounts of giant human fossils having been found. Additionally, very large tools have been found, which only very large people could have used.
There are a few photos of giant skeletons out there on the Web, but I am rather cautious about displaying any such photos.  But there are few that appear to be genuine. Of course, the 'believability' for a Bible literalist is a somewhat less daunting proposition: We know these giants have existed. 
In fact, since we know the world was amply populated with these creatures before the flood, we should be asking why all this evidence you're about to read of hasn't been made common knowledge.